Lights

Question
QUESTION: I understand what you were saying, I think. I discovered that the Power-Glo are 18000K. I had one 10000 or 12000K, so I pulled one of the Marine-Glo's which are actinic and replaced it with the 12000K because my candy canes do not seem to be doing well. My water is fine, I checked it, so I am thinking the light may not be bright enough. I am thinking about replacing the 2 Power-Glo's with a 10 or 12000K bulb. Do you think it best to have 2 actinics and 2 whites (once I changed bulbs) or would 3 whites and an actinic be better? Thanks for all your help.

ANSWER: Hi Debbie,
It really depends on the species, but I personally run an even mix in all of my systems, and have great growth and results, and have for years. If I have 4 bulbs I run 2 and 2, if 8 I run 4 and 4. Now I do have an 8 light system that all of the bulbs are the coralife 50/50 bulbs(standard flourescent fixture). It does seem to do better in general, regardless of species. But that is still the same lighting theory applied through a different bulb, thats all.

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QUESTION: I understand the mixture and that is what I thought. Seems everyone feels differently. I had someone tell me that the blue was more for color and really had no benefit. There are so many different options floating around. As far as the white, would I be better to replace the 18000K bulbs with 10000K or 12000K? Thanks again.

ANSWER: Oh yes, everyone has an opinion in aquaria, lol. The simple fact is that ALL corals are photosynthetic animals, they require specific lighting, the depth of their wild habitat dictates the required spectrum. The misconception that actinic lighting is simply for viewing pleasure is exactly that. A misconception. Yes, it is much more pleasing to the human eye, but deep water corals have to have it. HAVE TO. Its the way the water filters the light to them at greater depths.
If you are mixing the bulbs evenly(1 natural sun/1 actinic) I would go with the 12,000k. Saves a little money and you are going to get the green and blue spectrum from the actinics.

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QUESTION: It has helped alot. You may have answered the other day, but what is the difference between 420 and 460 actintic? Thanks again.

Answer
Actinic lighting peaks around the 420 nanometer range. The phosphor band's spectrum seems basically confined to the 400 to 480nm range, with most of the output between 410 and 435nm. The peak seems to be in the 415 to 420nm range(bluish violet/purple). 460nm is a cleaner blue with less violet/purple. I go for the 460nm generally, but if mixing lighting as we've been speaking about, it's a minimal difference. And the 420nm is generally a bit cheaper.